Garcinia gummi-gutta and one of its active compounds, hydroxycitric acid (HCA), have been promoted for weight loss or body building, but evidence is insufficient and mixed. 
Garcinia gummi-gutta, better known by its older name Garcinia cambogia, is a plant native to Southeast Asia. The fruit rinds are used as a flavoring agent and in traditional medicine. The extract and its active compound, HCA, can be found in many products promoted for weight loss or body building.
Preclinical animal studies suggest some benefits on weight and feed intake. However, human studies are limited and generally did not find effects on appetite, calorie intake, or weight loss. 
G. cambogia and HCA supplements may cause liver toxicity. Patients who have cancer, diabetes, depression, or other chronic diseases should use garcinia with caution as it may interact with medications.